.virtual-message-list {
  position: relative;
  width: 100%;
  height: 100%;
  overflow: hidden;
}

.message-measurer {
  width: 100%;
  padding: 4px 0;
}

/* 滚动到底部按钮 */
.scroll-to-bottom-button {
  position: absolute;
  bottom: 16px;
  right: 16px;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background-color: var(--primary-color);
  color: white;
  border: none;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  box-shadow: 0 2px 10px rgba(var(--primary-color-rgb), 0.3);
  opacity: 0.8;
  transform: translateY(0);
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  z-index: 10;
  font-size: 20px;
  line-height: 1;
}

.scroll-to-bottom-button:hover {
  opacity: 1;
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(var(--primary-color-rgb), 0.4);
}

.scroll-to-bottom-button span {
  font-weight: bold;
}

/* 历史消息加载指示器 */
.history-loading-indicator {
  position: absolute;
  top: 12px;
  left: 50%;
  transform: translateX(-50%);
  background-color: var(--card-bg);
  padding: 8px 16px;
  border-radius: 16px;
  box-shadow: var(--shadow-md);
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 12px;
  color: var(--text-secondary);
  z-index: 10;
  border: 1px solid var(--border-color);
  animation: fadeIn 0.3s ease-out;
}

.history-loading-indicator .loading-dot {
  width: 6px;
  height: 6px;
}

/* 自定义滚动条 */
.messages-list-container::-webkit-scrollbar {
  width: 6px;
  transition: width 0.3s;
}

.messages-list-container::-webkit-scrollbar-track {
  background: transparent;
}

.messages-list-container::-webkit-scrollbar-thumb {
  background-color: var(--border-color);
  border-radius: var(--border-radius-full);
  transition: background-color 0.3s, opacity 0.3s;
  opacity: 0.3;
}

.messages-list-container:hover::-webkit-scrollbar-thumb {
  opacity: 0.8;
}

.messages-list-container::-webkit-scrollbar-thumb:hover {
  background-color: var(--text-secondary);
}

/* 让滚动条在未使用时变小透明 */
.messages-list-container:not(:hover)::-webkit-scrollbar {
  width: 3px;
}

.messages-list-container:not(:hover)::-webkit-scrollbar-thumb {
  opacity: 0.1;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translate(-50%, -10px); }
  to { opacity: 1; transform: translate(-50%, 0); }
} 